JP2003321780A - Method for depositing film of superfine particles, piezoelectric actuator, and liquid discharge head - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a uniform piezoelectric film almost free from defects by preventing the agglomeration of superfine particle powder arranged in an aerosol forming chamber and depositing the film at a high speed. <P>SOLUTION: A mixed powder is prepared by pulverizing and mixing raw materials, then a calcined body is obtained by calcining the mixed powder, and a fine pulverized powder is produced by pulverizing the calcined body while adding a dispersant. Further, a thin film is formed by an aerosol gas deposition method using superfine particles of the fine pulverized powder. The film forming method comprises preparing the aerosol by mixing the superfine particles with a gas, and growing the film by allowing the superfine particles in the aerosol to collide on a substrate and is characterized in that the superfine particles are obtained by adding the dispersant to the powder of the superfine particles. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming ultrafine particles for growing a film on a substrate by spraying an aerosol containing ultrafine particles of ceramics or metal onto the substrate and causing the particles to collide with the substrate. Is. Further, the present invention relates to a piezoelectric actuator manufactured by this film forming method and a liquid ejection head using the same.

[0002]

2. Description of the Related Art Conventionally, the gas deposition method is, for example,
A film forming method using ultrafine particles described in Japanese Patent No. 1660799, in which a metal heating source and a vacuum container are arranged in the same manner as in the vacuum deposition method to form fine particles from metal vapor. It is a method of forming a film.

On the other hand, film formation using ultrafine particles of a ceramic material has also been proposed. A method for forming a ceramic film by such a method is described in, for example, Jpn. J. App
l. Phys. 36 (1997) 1159. The result shows that the PZT film was formed by colliding aerosolized lead zirconate titanate (PZT) powder with a Pt film-attached Si substrate, and performing a heat treatment at 750 ° C. The characteristics and piezoelectric characteristics have been measured and shown to function as a piezoelectric film.

[0004]

However, in particular, small ultrafine particles having a primary particle size of several μm or less are aggregated with each other due to the Van der Waals force, electrostatic attraction or the crosslinking effect of water to form particles of several tens to several hundreds μm. Agglomerated powder is formed. Since the agglomerated powder has a larger mass than the primary particles, it is difficult to suspend it by supplying or vibrating the gas, and the agitation of the ultrafine particles and the gas does not proceed in the aerosol forming chamber. The concentration of ultrafine particles inside was low. Therefore, there is a problem that the amount of ultrafine particles that collide with the substrate from the aerosol forming chamber via the transfer pipe and the nozzle per unit time is small, and the growth rate of the film becomes slow.

Even when the agglomerated powder is made into an aerosol, most of the agglomerated powder does not break into primary particles in the aerosol and collides with the substrate as the agglomerated powder as it is. Since the agglomerated powder has a large mass, it is not sufficiently accelerated, the kinetic energy when colliding with the substrate is small, the strong adhesion with the substrate or other particles cannot be obtained, and the substrate is not formed without forming a dense film. It sticks on top. Since the agglomerated powder attached on the formed film is easily lost, a defective portion is formed on the film, which makes it difficult to form a uniform film.

An object of the present invention is to solve the problems of the above-mentioned conventional method for forming fine particles, and to improve the film forming rate of the film by ultrafine particles and form a uniform film with few defective portions. It is to provide a possible film forming method. Another object is to provide a piezoelectric actuator having a uniform piezoelectric film with few defects and a liquid ejection head using the same.

[0007]

In order to achieve the above-mentioned object, the present invention prevents the aggregation of the ultrafine particle powder placed in the aerosol forming chamber, so that when the ultrafine particles are aerosolized, the ultrafine particles and the gas are Agitating can be suppressed, and it is possible to suppress the formation of defective parts on the film by collapsing the primary particles having a small mass among the ultrafine particles or the agglomerated powder that tends to become primary particles in the aerosol and colliding with the substrate, and to form a uniform film. Can be manufactured. By preventing agglomeration, the amount of agglomerated powder reaching and adhering to the substrate can be reduced, and a film forming method with a high film growth rate can be provided. By this film forming method, a uniform film with few defective portions can be formed. Further, by subjecting the piezoelectric film after film formation to heat treatment, most of the dispersant component contained in the piezoelectric film is volatilized, and deterioration of the characteristics of the piezoelectric film is prevented.

[1] The method for forming ultrafine particles of the present invention is as follows.
A method for forming an aerosol by stirring ultrafine particles with a gas, and growing the film on the substrate by colliding the ultrafine particles in the aerosol with the substrate, wherein the ultrafine particles are ultrafine particles. It is characterized in that a dispersant is added.

More specifically, the film forming method of the present invention is as follows.
First, the raw materials are crushed and mixed to prepare a mixed powder, and then the mixed powder is calcined to obtain a calcined body, and then the calcined body is crushed and a dispersant is added to obtain finely pulverized powder of ultrafine particles. Is produced, and a thin film is produced by using the ultrafine particles by an aerosol gas deposition method. Here, the average particle diameter of the ultrafine particles constituting the finely pulverized powder is preferably 0.1 μm or more and 1.0 μm or less.

[2] In the invention of the above [1], the dispersant is sodium pyrophosphate, sodium hexametaphosphate, sodium silicate, sodium carbonate, sodium polycarboxylic acid, ammonium salt, condensed naphthalenesulfonates. The multi-valued alcohol ester activator, the polyamide activator, and the diamine activator are at least one kind. The amount of the dispersant added is preferably 0.1% by weight or more and 0.6% by weight or less, more preferably 0.2% by weight or more and 0.4% by weight or less, with respect to the ultrafine particle powder. weight%
Add within the following range. In order to uniformly add the dispersant in the ultrafine powder, the addition amount is preferably 0.2% by weight or more. Further, in order to sufficiently volatilize the components of the dispersant by heat treatment of the piezoelectric film and suppress the residual amount to a negligible amount, the upper limit of the addition amount is preferably 0.4% by weight.

[3] In either of the above [1] or [2], it is desirable to perform heat treatment after growing a film on the substrate. Here, the heat treatment temperature of the film (particularly the piezoelectric film) can be 500 ° C. or higher and 1200 ° C. or lower, preferably 600 ° C. or higher and 800 ° C. or lower. When a material that becomes a piezoelectric body is used as the ultrafine particles, a large amount of the dispersant remains causes deterioration of piezoelectric strain characteristics. Therefore,
It is desirable to heat-treat after film formation by the film formation method of the present invention to evaporate or volatilize the dispersant. In particular, it is desirable to carry out the heat treatment under reduced pressure (in a vacuumed chamber) in order to suppress the residual amount of the dispersant component to the extent that the piezoelectric strain characteristics are not affected.

In the method for forming ultrafine particles according to any one of the above [1] to [3], before introducing the ultrafine particle powder to which the dispersant is added into the aerosol forming chamber, the ultrafine particle powder is heated to 100 ° C. or higher and 200 It is desirable to heat-dry at a temperature of ℃ or less. The effect of suppressing the agglomeration of ultrafine particles is further enhanced by performing heating and drying. However, if the ultrafine particles produced once are kept at a high heating temperature for a long period of time, compositional deviations may occur due to melting and evaporation of the components that make up the ultrafine particles. Is desirable.

[4] A piezoelectric actuator of the present invention is a piezoelectric actuator having electrodes on both sides of a piezoelectric film, wherein the piezoelectric film contains Na, Si, C, as impurity elements.
At least one selected from S and P is contained, and the content of the impurity element is 100 × 10 ⁻⁴ wt% or less in weight ratio. That is, when the unit weight (100% by weight) of the piezoelectric film, the content of the impurities is 1
It is suppressed to 00 × 10 ⁻⁴ wt% or less. There is a relation of 1 × 10 ⁻⁴ wt% = 1 × 10 ⁻⁴ mass% = 1 ppm (weight ratio). After adding a dispersant to ultrafine particles to prevent agglomeration and obtaining a uniform film with few defects, heat treatment is performed to evaporate the dispersant from the piezoelectric film and leave it as an impurity in the piezoelectric film. Suppress the ingredients of. At this time, by setting the content of the impurity element to 100 × 10 ⁻⁴ wt% or less in weight ratio, it is possible to avoid the deterioration of the piezoelectric strain characteristic.

[5] A liquid discharge head of the present invention is equipped with the piezoelectric actuator according to the above [4]. More specifically, the liquid discharge head includes a plurality of discharge liquid chambers arranged at a predetermined pitch, a discharge chamber liquid supply port provided in each of the discharge liquid chambers for supplying discharge liquid thereto, An injection nozzle hole provided on one side wall for partitioning each of the discharge liquid chambers, a vibration plate provided so as to partition the other side surface of each of the discharge liquid chambers, and the above [[ [4] and a piezoelectric actuator.

This liquid discharge head may have a structure having an electrode film on the vibrating plate and further a piezoelectric film on the electrode film. The thickness of the diaphragm is 1μm or more and 20μ
The thickness is preferably in the range of m or less, and more preferably in the range of 5 μm or more and 10 μm or less. In order to efficiently transmit the vibration energy of the piezoelectric film to the diaphragm, it is desirable that the thickness of the piezoelectric film be equal to the thickness of the diaphragm. Therefore, the thickness of the piezoelectric film is 1 μm or more and 20
It is preferably in the range of μm or less. More preferably, the thickness of the piezoelectric film is set within the range of 5 μm or more and 10 μm or less.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the film forming method according to the present invention, the produced piezoelectric actuator and an ejection head for an inkjet printer using the same will be described below. However, the present invention is not limited to these examples.

(Embodiment 1) FIG. 1 shows ultrafine particles according to the present invention.
FIG. 7 is a process chart showing a method of forming a piezoelectric film by a child. First,
Lead oxide (PbO), strontium carbonate (SrC)
O_Three), Titanium oxide (TiO_Two), Zirconium oxide
(ZrO_Two), Antimony oxide (Sb_TwoO_Three), Oxide
Ngan (MnO_Two) And aluminum oxide (Al_TwoO
_Three) Was used as a raw material. Chemical formula (Pb_0.9Sr_0.1)
(Zr_0.55Ti_0.45) O_ThreeWith
0.5% by weight of Sb as the main component of_TwoO_ThreeAnd 0.015 weight
% MnO _TwoAnd 0.015 wt% Al_TwoO_ThreeIncluding and
Each raw material is weighed so that it becomes 100% by weight and melted.
Use ethyl alcohol as a medium and use a ball mill for 2 hours.
And mixed while crushing (step S1). This mixed powder
The temperature is 800 ℃, and baked in the atmosphere for 2 hours,
Of lead zirconate titanate (PZT) satisfying the above components
A calcined body was obtained (step S2). Mechanically crush this calcined body
To produce PZT powder with the average particle size adjusted to 0.5 μm
(Step S3). In this crushing process,
As a powder, sodium hexametaphosphate is used per unit weight.
Or, add it to 0.3% by weight and pulverize it.
A fine powder was obtained.

Next, the moisture in the air adsorbed after firing is removed.
To remove, remove the PZT powder in an oven at a temperature of 150 ° C.
It was kept heated for 1 hour and dried sufficiently (step S
4). Then, add an appropriate amount of this PZT powder to the aerosol forming chamber.
Were filled (stored) (step S5), and
Pt / Ti / SiO by the aerosol deposition method ₂
A film was formed on the / Si substrate (step S6). substrate
Is SiO on the Si substrate₂Film, Ti film, Pt film
Layered was used. Ti film / Pt film is equivalent to the lower electrode
It is a laminated film. PZT film produced and laminated on Pt film
Has less agglomerated powder and less defects
I was able to.

[0019]

[Table 1]

In Table 1, Air means a clean gas having the same components as air. The unit of flow rate is (l / min)
≅Approximately 16.7 × 10 ⁻⁶ (m3 / s) A film forming apparatus for performing the aerosol deposition method will be described later in the description of FIG.

After forming a PZT film, that is, a piezoelectric film, a Ti (titanium) film and a Pt (platinum) film were coated as an upper electrode. Next, the laminated film of upper electrode / piezoelectric film / lower electrode was patterned to form a piezoelectric actuator. The dimension of the patterned piezoelectric film is 5mm in width and 10m in length.
m and the thickness is 15 μm. In addition, as a comparative example, when a film was formed using PZT powder without adding a dispersant, the thickness was less than 10 μm in the same film forming time, and the generated PZT film had more defects than the PZT film of Example 1. Was given.

Then, the PZT film (piezoelectric film) of Example 1 was heat-treated in the atmosphere at 500 ° C. for 1 hour (step S
7), the dispersant component was evaporated from the piezoelectric film. The heat treatment was performed so that the fine grain size immediately after film formation was increased so that the grain size of the piezoelectric film structure was in the range of 0.1 μm or more and 5 μm or less.

FIG. 2 is a schematic view showing a cross-sectional structure of an aerosol deposition apparatus which carries out the aerosol deposition method according to the present invention. This apparatus is equipped with a gas carrier pipe 51 for carrying oxygen, air or a mixed gas of these gases as a carrier gas from a gas cylinder (not shown) to an aerosol forming chamber 52, and a container containing an ultrafine particle powder 54 (PZT powder). A vibrating vibrating device 53, an aerosol forming chamber 52 that forms an aerosol in a solid gas permanent turbid state, an aerosol transfer pipe 55 that captures the formed aerosol and sends it to the nozzle 76, and a vacuum pump (not shown). And a film forming chamber 70 that is depressurized. In the film forming chamber 70,
An exhaust valve 71 connected to a vacuum pump, a substrate holder 73, an XY stage 72 for moving the substrate holder 73, and a nozzle 76 for ejecting aerosol are arranged. It should be noted that the lid 57 of the aerosol forming chamber may be provided with an exhaust valve and opened and closed as necessary to adjust the pressure in the aerosol forming chamber. The distance between the nozzle 76 having a rectangular opening with a length of 5 mm and a width of 0.5 mm and the substrate 74 was adjusted by a positioning means (not shown).

Next, a method of forming the piezoelectric film will be described. First, a carrier gas was introduced from a gas cylinder into a gas carrier pipe whose tip was buried in PZT powder. In the aerosol forming chamber 52, ultrafine particles of PZT powder are mixed with a carrier gas,
At the same time, the vibrating device 53 vibrates the aerosol forming chamber 52 to form an aerosol. This aerosol was carried to the nozzle 76 by the carrier gas through the aerosol carrying pipe 55 having one end opened in the aerosol forming chamber. Further, the film forming chamber 70 is evacuated to a depressurized state to generate a pressure difference between the aerosol forming chamber 52 and the film forming chamber 70, and the aerosol is accelerated at a high speed to be ejected from the nozzle 76, so that the substrate 74 is ejected. The PZT film 75 was formed by spraying. At the time of formation, by moving the substrate holder 73 with the XY stage 72, the nozzle 76 for the substrate holder 73 is moved.
Was moved to deposit ultrafine particles of PZT on the substrate to form a PZT film. The substrate holder 73 is a nozzle 76
About 10 mm at a speed of about 20 mm / min in the width direction of the opening of
I made one round trip. In the case of ultrafine particles having a particle size of PZT powder of 1 μm or less, the film formation rate increased and the adhesion strength with the substrate was improved. As the substrate 74, a Si substrate in which one surface was previously coated with a SiO ₂ film / Ti film / Pt film was used. More specifically, PZT is formed on the Pt film.
The film has been deposited.

FIG. 3 is a perspective view illustrating an outline of a part of an ink jet ejection head according to the present invention and a piezoelectric actuator provided therein. In this inkjet discharge head 2, the substrate forming the cavity is a Si substrate 27.
The SiO ₂ film formed by thermal oxidation on the Si substrate was used as the diaphragm 10. Next, a resist film (material: polyimide) was coated on the vibrating plate 10 and exposed, developed and fixed in a shape (frame) in which a portion corresponding to the lower electrode 26 was removed to form a resist pattern.

Next, a film to be the lower electrode 26 was formed over the entire surface and laminated on the vibration plate 10. The film serving as the lower electrode 26 was composed of a two-layer film including a Ti film (thickness: about 0.1 μm) and a Pt film (thickness: about 0.3 μm). Furthermore, the resist pattern and the one laminated on the upper surface of the resist pattern are used as a resist stripper (alkaline solvent, etc.).
It was removed by brushing while soaking in.

On the lower electrode 26 formed as described above, a resist pattern used together when forming the piezoelectric film by the aerosol deposition method is formed by the same method as described above, and then the piezoelectric film having a film thickness of 10 μm. Was deposited. A film to be the upper electrode 24 was formed on the upper surface of this piezoelectric film. The upper electrode film 24 is composed of a Ti film (thickness of about 0.1 μm) and a P film.
It was composed of a t-film (thickness: about 0.3 μm). After forming the upper electrode, all the resist pattern is removed, and the adjacent piezoelectric films 22 are formed.
The lower electrode 26 was separated in between.

Thereafter, a heat treatment is performed at 500 ° C. for 1 hour to evaporate most of the components of the dispersant, and the PZT particles are integrated with each other to form a piezoelectric film 22 having desired vibration characteristics.
Thus, a piezoelectric actuator 20 composed of the lower electrode 26 / piezoelectric film 22 / upper electrode 24 was obtained. The piezoelectric actuator 20 is a rectangular thin film having a width a, a length L, and a thickness d + (upper electrode thickness + lower electrode thickness), and is also called a piezoelectric element. Adjacent piezoelectric actuators 20 were arranged at a predetermined interval b. In addition, a similar piezoelectric actuator measurement dummy was prepared, and the same heat treatment was performed in parallel with the heat treatment of the example. Then, in the measurement dummy after the heat treatment, the upper electrode was removed by etching, and the exposed surface of the piezoelectric film was subjected to composition analysis by fluorescent X-ray analysis. In the piezoelectric film after the heat treatment, the impurity element P derived from sodium hexametaphosphate added to the PZT powder was added in a weight ratio of 30 × 10 3.
^-4 % by weight was found to be contained. Where 1
× 10 ^-4 % by weight = 1 × 10 ^-4 mass% = 1 ppm
(Weight ratio).

Next, in order to form the ink chamber 4 corresponding to the cavity, a predetermined resist mask was provided on the back surface of the Si substrate 27, and perforation was performed by anisotropic etching. The ink chamber 4 was punched at a position corresponding to the piezoelectric element.
By this perforation, the Si substrate 27 was processed into the partition wall 6.

Further, the bottom partition wall 8, the nozzle base 12 and the nozzle plate 14 are provided at the opening of the ink chamber so that the ejection nozzle hole 18 is connected to the ink chamber 4 to obtain the ink jet ejection head 2. Further, each ink chamber 4 is connected to the ink supply port 16 so that ink can be supplied.

Next, details of FIG. 3 will be described. The inkjet ejection head 2 includes a large number of elongated ink chambers 4 (also called liquid pressure chambers) having a rectangular cross section. The number of the ink chambers 4 depends on the size of the inkjet ejection head 2, and for example, several tens to several hundreds are provided. Ink chamber 4
Are arranged at a predetermined pitch P1, for example, at a pitch of several tens to several hundreds of μm. The adjacent ink chambers 4 are partitioned by the partition walls 6, and the bottom is partitioned by the bottom partition wall 8. The ceiling of each ink chamber 4 is partitioned by a vibration plate 10 having a relatively thin thickness, for example, a thickness of about 5 to 10 μm, and each vibration chamber 10 of each ink chamber 4 is unique as described later. It is able to vibrate.

A nozzle base 12 made of, for example, a relatively thick SUS plate is provided in the lower portion of the bottom partition wall 8, and a nozzle plate 14 made of, for example, a thin stainless steel plate is sequentially joined to this lower portion. In addition,
The bottom partition wall 8 may not be provided, and a part of the nozzle base 12 may be used instead of the bottom partition wall 8.

An ink supply port 16 is formed in the nozzle base 12 so as to correspond to each liquid pressure chamber 4, and is connected to each ink chamber 4 via an ink flow path (not shown). The bottom partition wall 8, the nozzle base 12, and the nozzle plate 14 that partition the ink chamber 4 are formed with minute jet nozzle holes 18 having a diameter of, for example, about 10 to 30 μm through them. These ejection nozzle holes 18 are provided so as to correspond to the respective ink chambers 4 (liquid pressure chambers) one by one.
By vibrating and pressurizing the inside of the liquid pressure chamber 4,
Ink droplets can be ejected from the ejection nozzle hole 18.

The ink jet ejection head shown in FIG. 3 is an example of a part of the arrangement in which a large number of piezoelectric actuators are arranged. Since it is difficult to show all the arrangement directions, the middle part is omitted with a wavy line. Further, the front surface of the ink chamber 4 (that is, the surface formed by the partition wall 6, the vibration plate 10, the bottom partition wall 8, the nozzle base 12, and the nozzle plate 14) corresponds to a cross section, but the ejection nozzle hole 18 and the like can be easily described. Therefore, hatching of the cross section is omitted in the figure.

The piezoelectric actuators 20, which are the features of the present invention, are provided above the respective vibration plates 10 one by one. This piezoelectric actuator 20 has a rectangular piezoelectric film 22 formed by an aerosol deposition method and patterned by a lift-off method. In the figure, an upper electrode made of, for example, a titanium-platinum composite film is provided on the upper surface side. 24 is joined, and a lower electrode 26 made of, for example, platinum or a titanium-platinum composite film is joined to the lower surface side. The thickness of each of the upper electrode 24 and the lower electrode 26 is 0.1.
μm. The width a of the piezoelectric actuator 20 was set within a range of about 60 to 95% of the ink chamber width. When the upper electrode is laminated on the piezoelectric body, its thickness should be 0.1
It is desirable that the thickness be ˜2 μm.

Next, a state in which the piezoelectric actuators are arranged on the substrate in the ink jet discharge head (liquid discharge head) 2 in FIG. 4 will be described. As shown in the plan view (a) of FIG. 4, one piezoelectric actuator 20
The (piezoelectric element) has a short side (width a) of 60 μm and a long side (length L) of 2 mm. About 1250 short sides a are formed in the long side direction (110 mm) of the SUS plate (substrate) at a pitch P1 (for example, 85 μm), and similarly, the short side direction (3
3 mm), a piezoelectric element having a long side L of 2 mm is arranged at a pitch P2.
(5 mm, for example) is formed in 5 rows. And
After punching the liquid pressure chamber (ink chamber or pressure chamber), it was cut into a size of 110 mm × 5 mm as shown in FIG. Alternatively, the figure (a) may be used as it is as a head of five stages (five rows). However, in this case, the size of the liquid ejection head can be reduced by setting the pitch P2 smaller than 5 mm. In FIG. 4, a part of the SUS plate in the long side direction is illustrated. When a voltage signal is individually applied between the upper electrode 24 and the lower electrode 26 of each piezoelectric actuator 20, the piezoelectric actuator 20 expands and contracts by the piezoelectric action,
The vibrating plate 10 is distorted and vibrated, and the pressure fluctuation causes the ink in the ink chamber 4 (liquid pressure chamber) to be ejected as an ink droplet from the ejection nozzle hole 18.

In this liquid discharge head, the material of the electrode can be selected from a plurality of materials as follows. The electrode is preferably a platinum-based alloy film (for example, platinum-rhodium alloy) or a laminated film of platinum-titanium or chromium-gold, which does not easily react with the lead element of the lead-based piezoelectric material at the maximum temperature during the manufacturing process, and further strontium ruthenium oxide is used. An oxide conductive material such as a material may be used.

FIG. 4C shows a perspective view of the ink jet printer. The inkjet discharge head 2 of Example 3 was installed on the head base (not shown) and provided inside the inkjet printer head 101. Tray 103
For the paper 105 (recording medium) inserted in the
The ink is ejected while scanning the inkjet printer head 101 in 2 to obtain a printed sheet from the discharge port 104.

Example 2 A piezoelectric actuator was manufactured in the same manner as in Example 1. However, regarding the production conditions, the type of dispersant used, etc. were changed. Table 2 shows examples of the dispersant used and the conditions. By adding a dispersant and heat-treating at 600 ° C. for 2 hours after film formation to sufficiently reduce the dispersant, a high-speed and uniform film is formed, and a piezoelectric film having few defects and a high piezoelectric strain constant is formed. I was able to get
Further, for each example, a dummy sample having the same structure was prepared, and after removing the upper electrode, the amount of impurities in the piezoelectric films was analyzed by fluorescent X-ray analysis. The unit of the amount of impurities was 10 ⁻⁴ wt%.
1 × 10 ⁻⁴ wt% = 1 × 10 ⁻⁴ mass% = 1 pp
m (weight ratio). The unit weight of the piezoelectric film is 100
When it is defined as weight%, it corresponds to 1 ppm = 0.0001 weight%. More preferably, each impurity element is 50 ppm or less. Note that the method for measuring the amount of residual impurities is not limited to fluorescent X-ray analysis, and other methods may be used.
For example, for other dummy samples manufactured under the same conditions, SIMS (Secondary Ion Mass Spectroscopy:
The composition can be analyzed by secondary ion mass spectrometry.

[0040]

[Table 2]

[0041]

[Table 3]

[0042]

As described above, the film forming method of the present invention and the piezoelectric actuator using the same can exhibit the following excellent operational effects. According to the film forming method of the present invention, aggregation of ultrafine particles can be suppressed, the film forming speed of the film is high, and a uniform film with few defects can be formed. Further, it is possible to obtain a piezoelectric actuator and an inkjet head using a uniform piezoelectric film with few defects.

[Brief description of drawings]

FIG. 1 is a process drawing for explaining a manufacturing method according to the present invention.

FIG. 2 is a schematic view showing an aerosol deposition apparatus to which the present invention is applied.

FIG. 3 is a perspective view showing an inkjet ejection head using the piezoelectric actuator of the present invention.

FIG. 4 is a plan view illustrating piezoelectric actuators arranged on a substrate, and a perspective view of an inkjet printer.

[Explanation of symbols]

2 inkjet discharge heads, 4 ink chambers, 6
Partition wall, 8 bottom partition wall, 10 diaphragm, 12 nozzle base, 14 nozzle plate, 16 ink supply port, 18 ejection nozzle hole, 20 piezoelectric actuator, 22 piezoelectric film, 24 upper electrode, 26 lower electrode, 27 Si substrate, 51 Gas carrier pipe, 52 Aerosol forming chamber, 53 Vibrating device, 54 Ultra fine powder, 55 Aerosol carrier pipe, 57 Lid, 70 Membrane forming chamber, 71 Exhaust valve, 72 XY stage, 7
3 substrate holder, 74 substrate, 75 PZT film, 7
6 nozzles, 101 inkjet printer head,
102 main body, 103 trays, 105 sheets.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H01L 41/24 B41J 3/04 103H (72) Inventor Toru Abe 5200 Mikkajiri, Kumagaya-shi, Saitama Hitachi Metals Co., Ltd. F-term in Advanced Electronics Research Laboratories (reference) 2C057 AF93 AG16 AG39 AG44 AG52 AP14 AP58 AQ02 BA03 BA14 4K044 AA06 AB10 BA08 BA14 BB02 BB11 CA23 CA62

Claims (5)

[Claims] 1. A method for forming a film, wherein an ultrafine particle is stirred with a gas to produce an aerosol, and the ultrafine particle in the aerosol is caused to collide with the substrate to grow a film on the substrate. A method for forming ultra-fine particles, which comprises adding a dispersant to fine particles. 2. The dispersant according to claim 1, wherein the dispersant is sodium pyrophosphate, sodium hexametaphosphate, sodium silicate, sodium carbonate, sodium polycarboxylic acid, ammonium salt, condensed naphthalene sulfonates, multi-value alcohol ester. At least 1 selected from the group of activators, polyamide activators and diamine activators
A method for forming ultra-fine particles, characterized in that it is a seed. 3. The method for forming ultrafine particles according to claim 1, wherein a heat treatment is performed after the film is grown on the substrate. 4. A piezoelectric actuator having electrodes on both sides of a piezoelectric film, wherein the piezoelectric film contains Na as an impurity element.
It contains at least one selected from Si, C, S, and P, and the content of the impurity element is 100 × 10 6 by weight.
^-4 % by weight or less, a piezoelectric actuator. 5. A liquid ejection head comprising the piezoelectric actuator according to claim 4.